Effects of prone and supine positions on sleep state and stress responses in preterm infants

Aim: The purpose of the study is to assess the influence of prone or supine position on sleep states and on withdrawal and approach reactions of preterm infants. Methods: Thirty-two preterm infants from Meir Medical Center, Israel, mean post menstrual age 30.37. ± 2.57, mean birth weight 1250. g. ± 313.86, participated in the study. Infants were studied during 48. h. Positions (prone and supine) were alternated every 3-4. h after feedings. Sleep states were assessed by Actigraph measurement and by two daily 30-min Naturalistic Observations of Newborn Behavior (NONB) to confirm sleep states and for recording the behavioral reactions (approach and withdrawal). Results: In the prone position there were more approach reactions as compared to withdrawal reactions (p< .001) while in the supine position, the approach and withdrawal reactions were comparable. In the prone position more sleep patterns (deep sleep, light sleep, drowsy) were observed as opposed to more awake patterns (quiet awake, active awake and agitated fussy) that were seen in the supine position. Conclusions: Clinical implications encourage placing the preterm infant in the prone position while in the NICU. This enables important achievements such as longer periods of quality sleep, and production of adaptive self-regulatory reactions.